Delete the Eino model adapters, callbacks, middleware, orchestration,
summarization and single-agent runner together with their dependencies.
Chat, batch tasks, workflow Agent nodes and sub-agents now share the Pi
runtime, and dispatch is a single code path instead of an engine switch.
Configuration migrates eino_middleware/eino_skills to runtime/skills and
drops the retired callback settings while old files still load. Settings,
i18n and docs describe Pi only. Also carry the Pi follow-up fixes: empty
required lists are omitted from tool schemas, historical tool results stay
with their call batch, model proxies work over HTTP/1.1, single-query
retrieval skips query expansion, and finalization docs match Pi lifecycle
events.
Introduce an isolated Node worker that hosts the Pi SDK while Go keeps
business state, permissions, MCP execution, evidence and delivery checks.
The worker is published per source fingerprint, streams events back to Go
and supports tool callbacks, cancellation, session resume and per-model
transport settings.
Agent dispatch, tool search, plan/task tools and migration controls are
wired on top of it: large tool catalogs load through Pi tool_search, the
conversation task board keeps its existing tools, and legacy mode/route
values still resolve. Workflow gains a native DAG with versioned JSON
checkpoints, and knowledge retrieval moves to native documents, splitter,
HTTP embeddings, vector search and reranking.
Sycun